{"id":23,"date":"2021-05-23T21:46:55","date_gmt":"2021-05-23T13:46:55","guid":{"rendered":"http:\/\/121.5.220.128\/wordpress\/?p=23"},"modified":"2021-11-30T20:48:28","modified_gmt":"2021-11-30T12:48:28","slug":"%e6%96%87%e4%bb%b6%e5%9f%ba%e7%a1%80%e6%a0%bc%e5%bc%8f","status":"publish","type":"post","link":"http:\/\/101.34.19.194\/?p=23","title":{"rendered":"\u6587\u4ef6\u57fa\u7840\u683c\u5f0f"},"content":{"rendered":"

\u5e38\u89c1\u6587\u4ef6\u5934\u3001\u6587\u4ef6\u5c3e<\/span><\/h2>\n
\n\n\n\n\n\n\n\n\n\n\n\n\n\n
\u6587\u4ef6\u683c\u5f0f<\/span><\/span><\/th>\n\u6587\u4ef6\u5934<\/span><\/span><\/th>\n\u6587\u4ef6\u5c3e<\/span><\/span><\/th>\n<\/tr>\n<\/thead>\n
JPEG<\/span><\/span><\/td>\nFF D8 FF<\/span><\/span><\/td>\nFF D9<\/span><\/span><\/td>\n<\/tr>\n
PNG<\/span><\/span><\/td>\n89 50 4E 47 0D 0A 1A 0A 00 00 00 0D<\/span><\/span><\/td>\nAE 42 60 82<\/span><\/span><\/td>\n<\/tr>\n
GIF<\/span><\/span><\/td>\n47 49 46 38<\/span><\/span><\/td>\n00 3B<\/span><\/span><\/td>\n<\/tr>\n
ZIP<\/span><\/span><\/td>\n50 4B 03 04<\/span><\/span><\/td>\n50 4B<\/span><\/span><\/td>\n<\/tr>\n
RAR<\/span><\/span><\/td>\n52 61 72 21<\/span><\/span><\/td>\n<\/td>\n<\/tr>\n
tar.gz<\/span><\/span><\/td>\n1F 8B 08<\/span><\/span><\/td>\n<\/td>\n<\/tr>\n
pyc<\/span><\/span><\/td>\n03 F3 0D 0A<\/span><\/span><\/td>\n<\/td>\n<\/tr>\n
MP3<\/span><\/span><\/td>\nFF FB 92<\/span><\/span><\/td>\n<\/td>\n<\/tr>\n
pdf<\/span><\/span><\/td>\n255044462D312E<\/span><\/span><\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<\/figure>\n

PNG<\/span><\/h3>\n
    \n
  • \n

    \u56fe\u79cd\uff1a<\/span>jpg<\/span><\/strong><\/span> \u56fe\u7247\u6709\u6587\u4ef6\u5c3e\u6807\u8bc6 <\/span>FF D9<\/span><\/strong><\/span>\uff0c\u800c\u56fe\u7247\u67e5\u770b\u5668\u53ea\u8bfb\u53d6 <\/span>FF D9<\/span><\/strong><\/span> \u4e4b\u524d\u7684\u6570\u636e\u663e\u793a\u4e3a\u56fe\u7247\uff0c\u56e0\u6b64 <\/span>FF D9<\/span><\/strong><\/span> \u4e4b\u540e\u7684\u7a7a\u95f4\u80fd\u591f\u5b58\u653e\u9690\u85cf\u6570\u636e\uff1b<\/span>png<\/span><\/strong><\/span> \u7684\u672b\u5c3e <\/span>00 00 00 00 49 45 4e 44 ae 42 60 82<\/span><\/strong><\/span> \u5145\u5f53\u6587\u4ef6\u5c3e\u6807\u8bc6\uff0c\u60c5\u51b5\u7c7b\u4f3c<\/span><\/p>\n<\/li>\n

  • \n

    LSB\u9690\u5199<\/span><\/strong><\/span>\uff1a\u5c06\u6570\u636e\u85cf\u533f\u5728\u6700\u4f4e\u6709\u6548\u4f4d\uff0c\u56e0\u6b64\u53ea\u9002\u5408 <\/span>\u65e0\u635f\u538b\u7f29 <\/span>png<\/code><\/span><\/strong><\/span> \u6216 <\/span>\u65e0\u538b\u7f29 <\/span>bmp<\/code><\/span><\/strong><\/span> \u56fe\u7247\u683c\u5f0f<\/span><\/p>\n<\/li>\n<\/ul>\n

    png \u6587\u4ef6\u4e3b\u8981\u75314\u5927\u5757\uff08Chunk\uff09\u7ec4\u6210\uff1a<\/span>\n\u200b<\/span>\n\u6587\u4ef6\u5934\u6570\u636e\u5757IHDR\uff08header chunk\uff09<\/span>\n\u8c03\u8272\u677f\u6570\u636e\u5757PLTE\uff08palette chunk\uff09<\/span>\n\u56fe\u50cf\u6570\u636e\u5757IDAT\uff08data chunk\uff09<\/span>\n\u56fe\u50cf\u7ed3\u675f\u6570\u636e\u5757IEND\uff08trailer chunk\uff09<\/span><\/pre>\n
    \n
    \n<\/div>\n
    IDHR\u5757<\/span><\/strong><\/span><\/h4>\n
    IHDR Chunk\u53c8\u79f0\u4e3a<\/span>\u56fe\u7247\u6587\u4ef6\u5934\u6570\u636e\u5757\uff08image header chunk\uff09<\/span><\/strong><\/span>\uff0c\u662f <\/span>png<\/code><\/span> \u56fe\u7247\u7684\u7b2c\u4e00\u4e2achunk\uff0c\u4e00\u5f20 <\/span>png<\/code><\/span> \u56fe\u7247<\/span>\u6709\u4e14\u4ec5\u6709<\/span><\/strong><\/span>\u4e00\u4e2aIHDR Chunk<\/span><\/p>\n
    \"img\"<\/div><\/span><\/p>\n
    png \u6587\u4ef6\u5934\u6807\u8bc6 89 50 4E 47 0D 0A 1A 0A<\/pre>\n
    \u56fe\u7247\u5bbd\u5ea6\u4e3a <\/span>00 00 01 f4<\/span><\/strong><\/span>\uff0c\u5373 <\/span>500<\/span><\/strong><\/span> \u50cf\u7d20<\/span><\/p>\n
    \u9ad8\u5ea6\u4e3a <\/span>00 00 01 a4<\/span><\/strong><\/span>\uff0c\u5373 <\/span>420<\/span><\/strong><\/span> \u50cf\u7d20<\/span><\/p>\n
    CRC\u7801\u4e3a <\/span>cb d6 df 8a<\/span><\/strong><\/span><\/p>\n
    PNG CRC\u7206\u7834<\/span><\/strong><\/span><\/p>\n
    import binascii\nimport struct\n\nmisc = open(\"2.png\",\"rb\").read()\n\nfor h in range(1024):\n data = misc[12:20] + struct.pack('>i',h)+ misc[24:29]\n crc32 = binascii.crc32(data) & 0xffffffff\n if crc32 == 0xcbd6df8a:\n     print h<\/pre>\n
    IDAT\u5757<\/span><\/strong><\/span><\/h4>\n
    \u56fe\u50cf\u6570\u636e\u5757IDAT(image data chunk)\uff1a\u5b83\u5b58\u50a8\u5b9e\u9645\u7684\u6570\u636e\uff0c\u5728\u6570\u636e\u6d41\u4e2d\u53ef\u5305\u542b\u591a\u4e2a\u8fde\u7eed\u987a\u5e8f\u7684\u56fe\u50cf\u6570\u636e\u5757\u3002<\/span><\/p>\n
    IDAT\u5b58\u653e\u7740\u56fe\u50cf\u771f\u6b63\u7684\u6570\u636e\u4fe1\u606f\uff0c\u56e0\u6b64\uff0c\u5982\u679c\u80fd\u591f\u4e86\u89e3IDAT\u7684\u7ed3\u6784\uff0c\u7528\u6237\u5c31\u53ef\u4ee5\u5f88\u65b9\u4fbf\u7684\u751f\u6210PNG\u56fe\u50cf<\/span><\/p>\n
    IEND\u5757<\/span><\/strong><\/span><\/h4>\n
    \u6bcf\u4e2a\u6b63\u5e38\u7684 <\/span>png<\/code><\/span> \u56fe\u7247\u6587\u4ef6\u7684<\/span>IEND Chunk<\/span><\/strong><\/span>\u90fd\u662f<\/span>\u56fa\u5b9a<\/span><\/strong><\/span>\u7684<\/span><\/p>\n
    00 00 00 00 49 45 4e 44 ae 42 60 82<\/pre>\n
    \u6bcf\u4e2a <\/span>png<\/code><\/span> \u6587\u4ef6\u7684<\/span>IEND Chunk<\/span><\/strong><\/span>\u90fd\u662f <\/span>00 00 00 00 49 45 4e 44 ae 42 60 82<\/code><\/span>\uff0c\u5360<\/span>12<\/span><\/strong><\/span>\u5b57\u8282\uff0c\u5b83\u4f5c\u4e3a <\/span>png<\/code><\/span> \u6587\u4ef6\u7684<\/span>\u6587\u4ef6\u5c3e\u6807\u8bc6<\/span><\/strong><\/span><\/p>\n
    BMP<\/span><\/h3>\n
    BMP\u6587\u4ef6\u75314\u90e8\u5206\u7ec4\u6210\uff1a<\/span><\/p>\n
      \n
    1. \n
      \u4f4d\u56fe\u6587\u4ef6\u5934(bitmap-file header)<\/span><\/p>\n<\/li>\n
    2. \n
      \u4f4d\u56fe\u4fe1\u606f\u5934(bitmap-informationheader)<\/span><\/p>\n<\/li>\n
    3. \n
      \u989c\u8272\u8868(color table)<\/span><\/p>\n<\/li>\n
    4. \n
      \u989c\u8272\u70b9\u9635\u6570\u636e(bits data)<\/span><\/p>\n<\/li>\n<\/ol>\n
      24\u4f4d\u771f\u5f69\u8272\u4f4d\u56fe\u6ca1\u6709\u989c\u8272\u8868\uff0c\u6240\u4ee5\u53ea\u67091\u30012\u30014\u8fd9\u4e09\u90e8\u5206<\/span><\/p>\n
      \u4f4d\u56fe\u4fe1\u606f\u5934<\/span><\/strong><\/span><\/h3>\n
      \n\n\n\n\n\n\n\n\n\n
      \u540d\u79f0<\/span><\/span><\/th>\n\u5360\u7528\u7a7a\u95f4<\/span><\/span><\/th>\n\u5185\u5bb9<\/span><\/span><\/th>\n\u5b9e\u9645\u6570\u636e<\/span><\/span><\/th>\n<\/tr>\n<\/thead>\n
      biSize<\/span><\/strong><\/span><\/span><\/td>\n4\u5b57\u8282<\/span><\/span><\/td>\n\u4f4d\u56fe\u4fe1\u606f\u5934\u7684\u5927\u5c0f\uff0c\u4e3a40<\/span><\/span><\/td>\n0x28(40)<\/span><\/span><\/td>\n<\/tr>\n
      biWidth<\/span><\/strong><\/span><\/span><\/td>\n4\u5b57\u8282<\/span><\/span><\/td>\n\u4f4d\u56fe\u7684\u5bbd\u5ea6\uff0c\u5355\u4f4d\u662f\u50cf\u7d20<\/span><\/span><\/td>\n0x200(512)<\/span><\/span><\/td>\n<\/tr>\n
      biHeight<\/span><\/strong><\/span><\/span><\/td>\n4\u5b57\u8282<\/span><\/span><\/td>\n\u4f4d\u56fe\u7684\u9ad8\u5ea6\uff0c\u5355\u4f4d\u662f\u50cf\u7d20<\/span><\/span><\/td>\n0x200(512)<\/span><\/span><\/td>\n<\/tr>\n
      biPlanes<\/span><\/strong><\/span><\/span><\/td>\n2\u5b57\u8282<\/span><\/span><\/td>\n\u56fa\u5b9a\u503c1<\/span><\/span><\/td>\n1<\/span><\/span><\/td>\n<\/tr>\n
      biBitCount<\/span><\/strong><\/span><\/span><\/td>\n2\u5b57\u8282<\/span><\/span><\/td>\n\u6bcf\u4e2a\u50cf\u7d20\u7684\u4f4d\u6570 1-\u9ed1\u767d\u56fe\uff0c4-16\u8272\uff0c8-256\u8272\uff0c24-\u771f\u5f69\u8272<\/span><\/span><\/td>\n0x18(24)<\/span><\/span><\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<\/figure>\n
      \n","protected":false},"excerpt":{"rendered":"
      \u5e38\u89c1\u6587\u4ef6\u5934\u3001\u6587\u4ef6\u5c3e \u6587\u4ef6\u683c\u5f0f \u6587\u4ef6\u5934 \u6587\u4ef6\u5c3e JPEG FF D8 FF FF D9 PNG 89 50 4E […]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":[],"categories":[2],"tags":[],"_links":{"self":[{"href":"http:\/\/101.34.19.194\/index.php?rest_route=\/wp\/v2\/posts\/23"}],"collection":[{"href":"http:\/\/101.34.19.194\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"http:\/\/101.34.19.194\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"http:\/\/101.34.19.194\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"http:\/\/101.34.19.194\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=23"}],"version-history":[{"count":3,"href":"http:\/\/101.34.19.194\/index.php?rest_route=\/wp\/v2\/posts\/23\/revisions"}],"predecessor-version":[{"id":322,"href":"http:\/\/101.34.19.194\/index.php?rest_route=\/wp\/v2\/posts\/23\/revisions\/322"}],"wp:attachment":[{"href":"http:\/\/101.34.19.194\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=23"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"http:\/\/101.34.19.194\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=23"},{"taxonomy":"post_tag","embeddable":true,"href":"http:\/\/101.34.19.194\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=23"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}